This invention relates to car washing apparatus, and more particularly to a mechanism for mounting a rotating brush which can contact the front and rear as well as the side of a vehicle passing the brush location.
Automatic car wash installations typically use rotating brushes to clean the surface of the vehicle. Some installations employ separate brushes to clean each side and additional brushes to clean the front and rear of the vehicle. There has been some effort made to develop car wash apparatus in which a single brush can clean the front and rear of the vehicle as well as one side. This is known as a wrap-around brush construction. In such apparatus a pair of rotary brushes are typically carried on arms positioned in sequential order on opposite sides of the track along which the vehicle is moved. As the vehicle passes along the track, the arms are moved so that each of the brushes will first contact the front of the car and then scrub laterally and outwardly from the center of the car towards one side. As the vehicle continues to move, the brushes will contact the side of the car and finally will return towards the center of the car and scrub the back of the car in doing so.
Examples of such wrap-around brush constructions are found in U.S. Pat. No. 3,350,733 issued Nov. 7, 1967 to D. C. Hanna, U.S. Pat. No. 3,570,034 issued Mar. 17, 1971 to Lanfrankie and U.S. Pat. No. 3,772,725 issued Nov. 20, 1973 to Shelstad. In the latter patent, the rotating brush is mounted on a carriage which travels along a boom whose free end is inclined downward and towards the center of the path of travel of the vehicle. The movement of the vehicle causes the boom to pivot towards the side so that the brush will contact the side of the vehicle as the vehicle passes the brush and the action of the rotating brush on the surface of the vehicle causes the carriage to move upwardly along the boom. Gravity is employed to return the carriage towards the free end of the boom so that the brush can follow along the rear of the vehicle as it passes. Such an arrangement relies totally on gravity and the action of the brush against the surface of the vehicle to properly position the brush. Because vehicles of different widths must be accommodated within the same car wash installation, the force produced by the action of the brush against the surface of the vehicles will vary and the retraction of the carriage along the boom will consequently also vary. Thus, with this arrangement the positioning of the brush end of the boom is unfortunately dependent in part upon the size of the vehicle being washed.
We have developed an automatic wrap-around type brush mechanism which is positioned by the action of the passing car and which is moved relative to a support by gravity but which will accommodate vehicles of different widths without affecting the proper positioning of the brush relative to the surfaces of the vehicle.